Description: The smooth sealed bearings of the Shimano BB-ES51 will keep you pedaling smoothly for miles. Features: *Octalink V2 compatible *Labyrinth seals keep contamination out of bearings *Standard BSA threading *22mm hollow spindle *Shimano Reference Number: BB-ES51 Specifications: *Spindle Length: 113 mm *Shell Width: 68 mm *Frame Interface: English *Crank Compatibility: Shimano Octalink V2​​